This image from a video released by a Taliban affiliated group Nov. 24, 2010, shows captive U.S. Army Sgt. Bowe Bergdahl alongside his suspected captor, Mullah Sangeen Zadran.

CBS

(CBS News) An American prisoner of war's captors reportedly said that the United States designating them as terrorists Friday would bring "hardships" to the U.S. soldier.

Senior commanders of the Haqqani network made the comments about Army Sgt. Bowe Bergdahl to the Reuters news agency after U.S. Secretary of State Hillary Clinton signed the paperwork officially classifying the group as a foreign terrorist organization.

"Until now we treated him very well but this move by the United States will of course created (sic) hardships for him," one commander told Reuters.

Bergdahl was captured in eastern Afghanistan in June 2009 by the Pakistan-based group. Army Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, told reporters last spring that the military was doing "everything in our power" to find Bergdahl.

Those efforts have reportedly included negotiating a swap of Taliban fighters in Guantanamo Bay, Cuba, for Bergdahl, his parents said earlier this year.

Clinton signed a report to Congress in Brunei Friday morning saying that the Haqqani met the statutory criteria to be designated a foreign terrorist organization, according to a senior State Department official. The designation makes it a crime to provide material support to the group and may lead to other nations and the Treasury Department taking action to cut off the group from its funding sources.

Bergdahl remains the sole American POW from the war in Afghanistan, a war with which he was reportedly disgusted. A Rolling Stone article published last spring cited emails Bergdahl sent to his parents, including one in which he said he was "ashamed to even be American."